Electric switch



J. F. CAVANAGH.

ELECTRIC SWITCH.

, APPLICATION FILED Aue.I5. 1918.

Patented J an. 20, 1920.-

ATTORNEY applied to a suitable UNITED STATES PATENT OFFICE.

JOHN F. CAVANAGH, OF MERIDEN, CONNECTICUT, ASSIGNOR TO THE CONNECTICUT TELEPHONE 8 ELECTRIC COMPANY, INC., OF MERIDEN, CONNECTICUT, A CORPO- RATION OF CONNECTICUT.

ELECTRIC SWITCH.

Specification of Letters Patent.

Patented Jan. 20, 1920.

Application filed August 15, 1918. Serial No. 250,019.

To all whom it may concern:

Be it known that 1, JOHN F. CAVANAGH, a citizen of the United States of America, residing at Meriden, Connecticut, have invented a new and useful Electric Switch, of which the following is a specification.

My invention relates to lighting switches and switches of the like characterused in automobiles and designed to be rendered inoperative when the machine is left unattended.

The objects of my invention have been to provide a particularly simple, inexpensive and at the same time, eflicient switch of this character.

Briefly stated, the invention may be said to reside in the combination with suitable switch contacts, of a removable controlling member therefor in the nature of a plunger and having both an offand an on position, while associated with the contacts. This structure enables the entire removal of the controlling plunger, or plug, for the purpose of rendering the switch inoperative and permits also of the plug remaining associated with the contacts in the off as well as the ,on position.

Other features of the invention and de tails of construction will appear as the specication proceeds.

In the accompanying drawing I have illustrated in a practical form one embodi ment of the invention, wherein V Figure 1, is a front view of the switch as face plate showing the same in the operative position.

Fig. 2, is a similar view with the controlling plug member removed and the switch in inoperative position. Fig. 3, is a detail controlling plug.

ig. 4, is a sectional view of the switch taken substantially on the plane of the line H of Fig. 1'."

In the particular structure disclosed the switch base 5 is in the form of a hollow open ended tubular member of insulating material partially closed at the front or open end thereof, by a late or disk 6 carrying a tubular guide s eeve or bushing 7 projecting into the hollow base. j

Within the hollow base are the separate spring contact fingers 8 and 9 and supported in this instance by being secured to the closed rear wall of the base.

view of the detached portion is engaged with the opposed springs,

as in Fig. 4, a circuit will be closed across the switch contacts and when the plunger is partly withdrawn to engage the insulating portion 11, with the spring contacts, the circuit will be interrupted across the switch contacts. The switch plunger will be retained in either the on or off position by the engagement of the contacts in the reduced or annularly grooved portions described and a snap action of the plunger in .passing from one position to the other is insured by reason of the raised ridge 13 be tween the annular grooves which ridge separates the conducting and nonconducting portions 12 and 11 respectively.

The structure described thus enables the switch as an entity being left in either the on or off position and in addition it is possible to'entirely withdraw the plug and wholly disconnect the same from the switch contacts. To accomplish this it is only necessary to exert sufiicient pull on the plug to overcome the holding tension of the spring contacts. If the switch is in the off position when the the plug ismerely withdrawn from engagement with 'thespring contacts in theend reduced portion 11, and if the-switch is in the on position when the plug is withdrawn, the plug is simply pulled longitudinally to carry both the reduced portions 11 plug is withdrawn,

and 12 out of engagement with the holding contacts.

The-plug is rengaged with the switch by simply inserting it through the tubular guide 7 and pushing it inward until it snaps into engagement with either the insulating preferably more or less'pointed as indicated at 14 to facilitate entry between the spring cilitating handling or operation of the same.

The switch may be mounted in various ways. In the illustration it is shown secured as by means of screws 16 on the back of a face plate 17.

My invention, it will be seen, provides a a practical and at the same time very simple and inexpensive switch for controlling a circuit, which can be rendered entirely inoperative by simply withdrawing the plug and which however may be left in the off or open-circuit position with the plug still in place. This is very desirable for automobile lighting where the switch should be in condition for instant operation by the driver of the car and should be capable of being rendered inoperative when the driver leaves the car.

I claim 1. In a device of the character described, abase, a face plate attached to one end of said base and having a guide aperture for a plug, spring contacts mounted in said base mounted ing releasably relatively smooth to each other, terminals for said spring contacts,

in said aperture and guided thereby, said plug having an insulating portion near one end, said portion having an annular depression, a portion of conducting material on said insulating portion between the ends of'the latter and having an annular depression, said plug being of such conformation that it may be entirely withdrawn from said guide aperture, and said plug beheld in the off or the on position by means of the spring contacts engaging in said annular depressions.

2. As'an article of manufacture, a plug for electric switches having near one end a portion of insulating material, said portion having an annular depression,a portion of conducting material mounted on said portion of insulating material between the ends of the latter and having an annular depression, a relatively smooth portion adjacent said portion of insulating material, said smooth portion being of a diameter at least as great as any diameter of the plug between the portion and the aforesaid end of the plug, and a head upon the end of the plug remote from said first mentioned end.

JOHN F. CAVANAGH. 

